In a cardiac catheter test, a contrast agent is introduced to a patient using an injector head, and the test is done while imaging the affected part. Utilizing a coronary angiography of providing images of cardiac blood vessels, an operation of blood vessel is performed for widening a narrowed lesion by catheter method. Utilizing left ventricular angiogram imaging the left ventricle of the heart, behavior of cardiac muscle around the left ventricle is tested, by monitoring systole and diastole states of the heart.
Examples of such an injector head are disclosed, for example, in Japanese Patent Laying-Open Nos. 10-165396 (Patent Document 1) and 10-244002 (Patent Document 2).
When a test is to be conducted using an injector head, an operation referred to as “priming” is required, for expelling air from a syringe attached to the injector head in advance.
At the time of priming, in order to efficiently expel air from the syringe, it is necessary to have the injector head assume an upward facing orientation (priming orientation), so that a through hole provided at the front end of the syringe faces upward.
On the other hand, when introducing a contrast agent to the patient, the injector head must be rotated broadly to have the injector head in a downward facing orientation (contrast agent injectable orientation), so that the through hole provided at the front end of the syringe faces downward.
To the through hole provided at the front end of the syringe, a tube leading to the patient is coupled. When an operator selects the priming orientation or the contrast agent injectable orientation of the injector head, the injector head is rotated broadly with the tube kept coupled to the through hole of the injector head.
If the injector head is rotated broadly, the tube coupled to the through hole of the syringe also swings significantly. Therefore, the tube must have a margin in its length. If the tube is adapted to have an enough margin in length, the engineer or operator must be very careful to avoid any contact between the tube and other devices. In order to avoid contact between the tube and other devices, arrangement of devices must also be taken care of.